1/*
  2 *  acpi_numa.c - ACPI NUMA support
  3 *
  4 *  Copyright (C) 2002 Takayoshi Kochi <t-kochi@bq.jp.nec.com>
  5 *
  6 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  7 *
  8 *  This program is free software; you can redistribute it and/or modify
  9 *  it under the terms of the GNU General Public License as published by
 10 *  the Free Software Foundation; either version 2 of the License, or
 11 *  (at your option) any later version.
 12 *
 13 *  This program is distributed in the hope that it will be useful,
 14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 16 *  GNU General Public License for more details.
 17 *
 18 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 19 *
 20 */
 21#include <linux/module.h>
 22#include <linux/init.h>
 23#include <linux/kernel.h>
 24#include <linux/types.h>
 25#include <linux/errno.h>
 26#include <linux/acpi.h>
 27#include <linux/numa.h>
 28#include <linux/nodemask.h>
 29#include <linux/topology.h>
 30
 31#define PREFIX "ACPI: "
 32
 33#define ACPI_NUMA	0x80000000
 34#define _COMPONENT	ACPI_NUMA
 35ACPI_MODULE_NAME("numa");
 36
 37static nodemask_t nodes_found_map = NODE_MASK_NONE;
 38
 39/* maps to convert between proximity domain and logical node ID */
 40static int pxm_to_node_map[MAX_PXM_DOMAINS]
 41			= { [0 ... MAX_PXM_DOMAINS - 1] = NUMA_NO_NODE };
 42static int node_to_pxm_map[MAX_NUMNODES]
 43			= { [0 ... MAX_NUMNODES - 1] = PXM_INVAL };
 44
 45unsigned char acpi_srat_revision __initdata;
 46
 47int pxm_to_node(int pxm)
 48{
 49	if (pxm < 0)
 50		return NUMA_NO_NODE;
 51	return pxm_to_node_map[pxm];
 52}
 53
 54int node_to_pxm(int node)
 55{
 56	if (node < 0)
 57		return PXM_INVAL;
 58	return node_to_pxm_map[node];
 59}
 60
 61static void __acpi_map_pxm_to_node(int pxm, int node)
 62{
 63	if (pxm_to_node_map[pxm] == NUMA_NO_NODE || node < pxm_to_node_map[pxm])
 64		pxm_to_node_map[pxm] = node;
 65	if (node_to_pxm_map[node] == PXM_INVAL || pxm < node_to_pxm_map[node])
 66		node_to_pxm_map[node] = pxm;
 67}
 68
 69int acpi_map_pxm_to_node(int pxm)
 70{
 71	int node;
 72
 73	if (pxm < 0 || pxm >= MAX_PXM_DOMAINS)
 74		return NUMA_NO_NODE;
 75
 76	node = pxm_to_node_map[pxm];
 77
 78	if (node == NUMA_NO_NODE) {
 79		if (nodes_weight(nodes_found_map) >= MAX_NUMNODES)
 80			return NUMA_NO_NODE;
 81		node = first_unset_node(nodes_found_map);
 82		__acpi_map_pxm_to_node(pxm, node);
 83		node_set(node, nodes_found_map);
 84	}
 85
 86	return node;
 87}
 88
 89/**
 90 * acpi_map_pxm_to_online_node - Map proximity ID to online node
 91 * @pxm: ACPI proximity ID
 92 *
 93 * This is similar to acpi_map_pxm_to_node(), but always returns an online
 94 * node.  When the mapped node from a given proximity ID is offline, it
 95 * looks up the node distance table and returns the nearest online node.
 96 *
 97 * ACPI device drivers, which are called after the NUMA initialization has
 98 * completed in the kernel, can call this interface to obtain their device
 99 * NUMA topology from ACPI tables.  Such drivers do not have to deal with
100 * offline nodes.  A node may be offline when a device proximity ID is
101 * unique, SRAT memory entry does not exist, or NUMA is disabled, ex.
102 * "numa=off" on x86.
103 */
104int acpi_map_pxm_to_online_node(int pxm)
105{
106	int node, n, dist, min_dist;
107
108	node = acpi_map_pxm_to_node(pxm);
109
110	if (node == NUMA_NO_NODE)
111		node = 0;
112
113	if (!node_online(node)) {
114		min_dist = INT_MAX;
115		for_each_online_node(n) {
116			dist = node_distance(node, n);
117			if (dist < min_dist) {
118				min_dist = dist;
119				node = n;
120			}
121		}
122	}
123
124	return node;
125}
126EXPORT_SYMBOL(acpi_map_pxm_to_online_node);
127
128static void __init
129acpi_table_print_srat_entry(struct acpi_subtable_header *header)
130{
131
132	ACPI_FUNCTION_NAME("acpi_table_print_srat_entry");
133
134	if (!header)
135		return;
136
137	switch (header->type) {
138
139	case ACPI_SRAT_TYPE_CPU_AFFINITY:
140#ifdef ACPI_DEBUG_OUTPUT
141		{
142			struct acpi_srat_cpu_affinity *p =
143			    (struct acpi_srat_cpu_affinity *)header;
144			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
145					  "SRAT Processor (id[0x%02x] eid[0x%02x]) in proximity domain %d %s\n",
146					  p->apic_id, p->local_sapic_eid,
147					  p->proximity_domain_lo,
148					  (p->flags & ACPI_SRAT_CPU_ENABLED)?
149					  "enabled" : "disabled"));
150		}
151#endif				/* ACPI_DEBUG_OUTPUT */
152		break;
153
154	case ACPI_SRAT_TYPE_MEMORY_AFFINITY:
155#ifdef ACPI_DEBUG_OUTPUT
156		{
157			struct acpi_srat_mem_affinity *p =
158			    (struct acpi_srat_mem_affinity *)header;
159			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
160					  "SRAT Memory (0x%lx length 0x%lx) in proximity domain %d %s%s%s\n",
161					  (unsigned long)p->base_address,
162					  (unsigned long)p->length,
163					  p->proximity_domain,
164					  (p->flags & ACPI_SRAT_MEM_ENABLED)?
165					  "enabled" : "disabled",
166					  (p->flags & ACPI_SRAT_MEM_HOT_PLUGGABLE)?
167					  " hot-pluggable" : "",
168					  (p->flags & ACPI_SRAT_MEM_NON_VOLATILE)?
169					  " non-volatile" : ""));
170		}
171#endif				/* ACPI_DEBUG_OUTPUT */
172		break;
173
174	case ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY:
175#ifdef ACPI_DEBUG_OUTPUT
176		{
177			struct acpi_srat_x2apic_cpu_affinity *p =
178			    (struct acpi_srat_x2apic_cpu_affinity *)header;
179			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
180					  "SRAT Processor (x2apicid[0x%08x]) in"
181					  " proximity domain %d %s\n",
182					  p->apic_id,
183					  p->proximity_domain,
184					  (p->flags & ACPI_SRAT_CPU_ENABLED) ?
185					  "enabled" : "disabled"));
186		}
187#endif				/* ACPI_DEBUG_OUTPUT */
188		break;
189	default:
190		printk(KERN_WARNING PREFIX
191		       "Found unsupported SRAT entry (type = 0x%x)\n",
192		       header->type);
193		break;
194	}
195}
196
197/*
198 * A lot of BIOS fill in 10 (= no distance) everywhere. This messes
199 * up the NUMA heuristics which wants the local node to have a smaller
200 * distance than the others.
201 * Do some quick checks here and only use the SLIT if it passes.
202 */
203static int __init slit_valid(struct acpi_table_slit *slit)
204{
205	int i, j;
206	int d = slit->locality_count;
207	for (i = 0; i < d; i++) {
208		for (j = 0; j < d; j++)  {
209			u8 val = slit->entry[d*i + j];
210			if (i == j) {
211				if (val != LOCAL_DISTANCE)
212					return 0;
213			} else if (val <= LOCAL_DISTANCE)
214				return 0;
215		}
216	}
217	return 1;
218}
219
220static int __init acpi_parse_slit(struct acpi_table_header *table)
221{
222	struct acpi_table_slit *slit = (struct acpi_table_slit *)table;
223
224	if (!slit_valid(slit)) {
225		printk(KERN_INFO "ACPI: SLIT table looks invalid. Not used.\n");
226		return -EINVAL;
227	}
228	acpi_numa_slit_init(slit);
229
230	return 0;
231}
232
233void __init __weak
234acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa)
235{
236	printk(KERN_WARNING PREFIX
237	       "Found unsupported x2apic [0x%08x] SRAT entry\n", pa->apic_id);
238	return;
239}
240
241
242static int __init
243acpi_parse_x2apic_affinity(struct acpi_subtable_header *header,
244			   const unsigned long end)
245{
246	struct acpi_srat_x2apic_cpu_affinity *processor_affinity;
247
248	processor_affinity = (struct acpi_srat_x2apic_cpu_affinity *)header;
249	if (!processor_affinity)
250		return -EINVAL;
251
252	acpi_table_print_srat_entry(header);
253
254	/* let architecture-dependent part to do it */
255	acpi_numa_x2apic_affinity_init(processor_affinity);
256
257	return 0;
258}
259
260static int __init
261acpi_parse_processor_affinity(struct acpi_subtable_header *header,
262			      const unsigned long end)
263{
264	struct acpi_srat_cpu_affinity *processor_affinity;
265
266	processor_affinity = (struct acpi_srat_cpu_affinity *)header;
267	if (!processor_affinity)
268		return -EINVAL;
269
270	acpi_table_print_srat_entry(header);
271
272	/* let architecture-dependent part to do it */
273	acpi_numa_processor_affinity_init(processor_affinity);
274
275	return 0;
276}
277
278static int __initdata parsed_numa_memblks;
279
280static int __init
281acpi_parse_memory_affinity(struct acpi_subtable_header * header,
282			   const unsigned long end)
283{
284	struct acpi_srat_mem_affinity *memory_affinity;
285
286	memory_affinity = (struct acpi_srat_mem_affinity *)header;
287	if (!memory_affinity)
288		return -EINVAL;
289
290	acpi_table_print_srat_entry(header);
291
292	/* let architecture-dependent part to do it */
293	if (!acpi_numa_memory_affinity_init(memory_affinity))
294		parsed_numa_memblks++;
295	return 0;
296}
297
298static int __init acpi_parse_srat(struct acpi_table_header *table)
299{
300	struct acpi_table_srat *srat = (struct acpi_table_srat *)table;
301
302	acpi_srat_revision = srat->header.revision;
303
304	/* Real work done in acpi_table_parse_srat below. */
305
306	return 0;
307}
308
309static int __init
310acpi_table_parse_srat(enum acpi_srat_type id,
311		      acpi_tbl_entry_handler handler, unsigned int max_entries)
312{
313	return acpi_table_parse_entries(ACPI_SIG_SRAT,
314					    sizeof(struct acpi_table_srat), id,
315					    handler, max_entries);
316}
317
318int __init acpi_numa_init(void)
319{
320	int cnt = 0;
321
322	/*
323	 * Should not limit number with cpu num that is from NR_CPUS or nr_cpus=
324	 * SRAT cpu entries could have different order with that in MADT.
325	 * So go over all cpu entries in SRAT to get apicid to node mapping.
326	 */
327
328	/* SRAT: Static Resource Affinity Table */
329	if (!acpi_table_parse(ACPI_SIG_SRAT, acpi_parse_srat)) {
330		acpi_table_parse_srat(ACPI_SRAT_TYPE_X2APIC_CPU_AFFINITY,
331				     acpi_parse_x2apic_affinity, 0);
332		acpi_table_parse_srat(ACPI_SRAT_TYPE_CPU_AFFINITY,
333				     acpi_parse_processor_affinity, 0);
334		cnt = acpi_table_parse_srat(ACPI_SRAT_TYPE_MEMORY_AFFINITY,
335					    acpi_parse_memory_affinity,
336					    NR_NODE_MEMBLKS);
337	}
338
339	/* SLIT: System Locality Information Table */
340	acpi_table_parse(ACPI_SIG_SLIT, acpi_parse_slit);
341
342	acpi_numa_arch_fixup();
343
344	if (cnt < 0)
345		return cnt;
346	else if (!parsed_numa_memblks)
347		return -ENOENT;
348	return 0;
349}
350
351static int acpi_get_pxm(acpi_handle h)
352{
353	unsigned long long pxm;
354	acpi_status status;
355	acpi_handle handle;
356	acpi_handle phandle = h;
357
358	do {
359		handle = phandle;
360		status = acpi_evaluate_integer(handle, "_PXM", NULL, &pxm);
361		if (ACPI_SUCCESS(status))
362			return pxm;
363		status = acpi_get_parent(handle, &phandle);
364	} while (ACPI_SUCCESS(status));
365	return -1;
366}
367
368int acpi_get_node(acpi_handle handle)
369{
370	int pxm;
371
372	pxm = acpi_get_pxm(handle);
373
374	return acpi_map_pxm_to_node(pxm);
375}
376EXPORT_SYMBOL(acpi_get_node);